The present subject matter relates to an engine having a combustion chamber, an inlet duct, which may be associated with the combustion chamber, which may be used to supply the combustion chamber with intake air, an inlet valve, which may be designed to close the inlet duct with respect to the combustion chamber in a first position and may be further configured to open wide an annular gap in a second position. The subject engine may further comprise an injector associated with the combustion chamber, for injecting fuel into a motor vehicle having said engine. The present subject matter may further relate to an injection method provided for the engine system described above.
Engines, or more specifically, internal combustion engines, that comprise an injection device arranged within an intake duct are known, one example approach is shown by Baeuerle et al. in DE 102008044244 A1. Therein, Baeuerle discloses an internal combustion engine comprising at least one combustion chamber that may be closed off by an inlet valve and at least one air intake duct leading to said inlet valve. The above mentioned prior art further comprises a fuel injection device, which includes a first and a second injection valve associated with the at least one combustion chamber for the metered injection of fuel into the at least one intake duct. In order to achieve a mixture preparation and ultimately combustion of the fuel/air mixture within the combustion chamber provided, the two injection valves are designed in such a way that the first injection valve discharges a widely spread cone-shaped spray pattern having a substantially large cone angle, and the provided second injection valve discharges a cone-shaped spray pattern that comprises a more acute cone angle relative to that of the first provided injection valve.
However, the inventors herein have recognized potential issues with such systems. As one example, fuel injectors may produce a spray pattern shaped like a solid cone. In producing a solid cone-shaped spray, the usefulness of the spray injectors may not be fully utilized. Specifically, when the fine liquid spray produced by the fuel injector comes into contact with a surface other than the intended target of the annular gap within the combustion chamber, such as the piston or the inlet valve, the previously fine mist may collect and form relatively larger sized droplets. When mixing air and fuel within a combustion chamber, it may be preferable to provide the liquid fuel in a relatively fine particulate form such that it may be easier to completely mix the fuel and the intake air in a more efficient manner.
In one example, the issues described above may be addressed by a method for injecting fuel into a combustion chamber of an engine, comprising; in response to opening an inlet valve associated with the combustion chamber, injecting fuel into the combustion chamber through an injector coupled to an inlet duct, wherein the injected fuel has a geometry of a hollow cone. In this way, a hollow, cone-shaped inlet duct may enable the possibility of using the entire annular gap of a combustion chamber within an internal combustion engine for injection of a fuel. This may result in a larger quantity of fuel being introduced into the combustion chamber.
As one example, an embodiment of the present disclosure may comprise an internal combustion engine having a combustion chamber, an inlet duct associated with a combustion chamber for supplying the combustion chamber with intake air, an inlet valve which may be configured to close an inlet duct with respect to the combustion chamber in a first position and to open wide an annular gap with respect to the combustion chamber in a second position, an injector associated with a combustion chamber for injecting fuel, and a control unit for controlling the injector.
According to the present subject matter, the control unit may be configured to detect a second position of an inlet valve and may be further configured to trigger an injection process of an injector when an inlet valve is in a second position. In a second position, an injector may be arranged within an inlet duct and may be configured to spray the fuel out of an inlet duct and through an annular gap within a combustion chamber during an injection process. In one example, the injector may comprise a hollow cone shape, which may be configured to discharge the fuel in a formation which may comprise the geometry of a hollow cone. In this way, a hollow cone-shaped spray pattern may enable the possibility of using the supplied fuel more effectively, and it may be possible to inject fuel without unnecessary wetting of other surfaces within an inlet duct or inlet valve of a provided internal combustion engine.
It should be understood that the summary above is provided to introduce in simplified form a selection of concepts that are further described in the detailed description. It is not meant to identify key or essential features of the claimed subject matter, the scope of which is defined uniquely by the claims that follow the detailed description. Furthermore, the claimed subject matter is not limited to implementations that solve any disadvantages noted above or in any part of this disclosure.